#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <string>
using namespace std;


int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    int rawInput,n , cnt_val = 0 , result = 0; 
    char c; 
    cin>>n ; 
    while(n-->0 ){ 
        cin >> c; 
        if(c=='U')
            {
            cnt_val ++ ; 
            }
        else if(c=='D'){
            cnt_val -- ;
            if(cnt_val == -1){
                result ++ ;                
            }
            
        }
        
        
    }
    
    cout << result; 
    return 0;
}